The massive nodular cutaneous and soft tissues lesions of the right shoulder and the arm as the extramedullary manifestation of the advanced stage of multiple myeloma

Cutaneous and soft tissue involvement is a very rare manifestation of multiple myeloma. We are describing a woman with the huge multiple plasma cells infiltrations of the soft tissues and the skin of the right shoulder and the arm that had occurred 2.5 years after the diagnosis of multiple myeloma. In the case of the described patient there is a distinct correlation between the appearance of the nodular lesions in soft tissues and the underlying osteolytic changes found in the skeleton. We assumed that the fracture of the right humerus in the past was the beginning of the plasma cells dissemination in the adherent tissues. The skin changes in our patient appeared in the advanced stage of multiple myeloma. There was only transient improvement of cutaneous changes after the chemotherapy, despite the complete remission of the underlying disease in the bone marrow. Despite of the intensive treatment (chemotherapy, radiotherapy) the patient died 7 months after the first appearance of the skin changes.